Scan Quality and Entrance Skin Dose in Thoracic CT: A Comparison between Bismuth Breast Shield and Posteriorly Centered Partial CT Scans

Table 3

Summary of quantitative assessment of CT image quality with breast shield. Hounsfield units and standard deviation are compared in the anterior and posterior subcutaneous fat. Values are in Hounsfield units.

Location	Mean	Standard deviation	95% Confidence Interval for Mean	Paired 𝑡-Test 𝑃 value
Anterior; HU	−62.34	23.00	(−68.81,−55.87)	0.021
Posterior; HU	−81.91	55.90	(−97.64,−66.19)
Anterior; SD	12.98	11.64	(9.71,16.26)	0.027
Posterior; SD	14.84	14.58	(10.74,18.94)